Saturday, December 16, 2017

No Alien Signals Detected from Interstellar Visitor Oumuamua

No evidence of artificial signals emanating from the object so far detected by the Green Bank Telescope, but monitoring and analysis continue. Initial data are available for public inspection in the Breakthrough Listen archive.

 Breakthrough Listen – the initiative to find signs of intelligent life in the universe – is reporting preliminary results and making initial data available from its observations of the "interstellar visitor" ‘Oumuamua'.

Artist's concept of interstellar asteroid 1I/2017 U1 ('Oumuamua) as it passed through the solar system after its discovery in October 2017. The aspect ratio of up to 10:1 is unlike that of any object seen in our own solar system.
Artist's concept of interstellar asteroid 1I/2017 U1
Image credit: European Southern Observatory / M. Kornmesser

ʻOumuamua is a small object, estimated to be about 230 by 35 meters (800 ft × 100 ft) in size. It has a relatively high density, comparable to metal-rich rock, and a dark and very red color, similar to objects in the outer Solar System. 

ʻOumuamua is tumbling rather than smoothly rotating, and it is moving so fast through space relative to the Sun that there is no chance it originated in the Solar System. It also means that ʻOumuamua can not be captured into a solar orbit, so it will eventually leave the Solar System and resume traveling in interstellar space. ʻOumuamua's system of origin and the amount of time it has been traveling among the stars are unknown.

This animation shows the path of A/2017 U1, which is an asteroid -- or perhaps a comet -- as it passed through our inner solar system in September and October 2017. From analysis of its motion, scientists calculate that it probably originated from outside of our solar system.
Asteroid path animation
Credits: NASA/JPL-Caltech

The initial block of observations (the first of a planned four blocks) ran from 3:45pm to 9:45pm ET on Wednesday, December 13, using the Breakthrough Listen backend instrument on the Robert C. Byrd Green Bank Telescope in West Virginia. Listen observed ‘Oumuamua across four radio bands (corresponding to four of the radio receivers available at Green Bank, denoted L, S, X, and C), spanning billions of individual channels across the 1 to 12 GHz range.

In addition to calibration observations, the instrument accumulated 90 TB of raw data over a 2 hour observation of ‘Oumuamua itself. A search for signals that may be of artificial origin has begun, but despite the impressive computational power of the Breakthrough Listen computing cluster at Green Bank, the large data volumes mean that this will take some time to complete.

“It is great to see data pouring in from observations of this novel and interesting source,” said Andrew Siemion, Director of Berkeley SETI Research Center. “Our team is excited to see what additional observations and analyses will reveal”.

Cedit: European Southern Observatory / M. Kornmesser

The Breakthrough Listen "turboSETI" pipeline2 combs the data for narrow bandwidth signals that are drifting in frequency. By matching the rate at which these signals drift to the expected drift due to the motion of ‘Oumuamua (in addition to rejecting interfering signals from human technology that do not match the sky position of the primary target), the software attempts to identify any signals that might be coming from ‘Oumuamua itself.

No such signals have been detected, although the analysis is not yet complete. So far, data from the S-band receiver (covering frequencies from 1.7 to 2.6 GHz) has been processed, and analysis of the remaining three bands is ongoing. A subset of the S-band data is now available for public inspection in the Breakthrough Listen archive3, and additional data will be added as it becomes available.

This animation (annotated) shows the path of the interstellar asteroid 1I/2017 (`Oumuamua) through the Solar System. Observations with ESO's Very Large Telescope and others have shown that this unique object is dark, reddish in colour and highly elongated.

Credit: ESO, M. Kornmesser, L.Calcada. Music: Azul Cobalto

The data is stored in specialized formats, and analyzing it may be challenging for non-experts. We invite those who are interested to study the tutorial material4provided by the Breakthrough Listen science team at the University of California, Berkeley, SETI Research Center and to assist with the analysis not only of this intriguing object, but of the entire Breakthrough Listen dataset.

Breakthrough Listen is a scientific program in search for evidence of technological life in the Universe. It aims to survey one million nearby stars, the entire galactic plane and 100 nearby galaxies at a wide range of radio and optical bands.

The Breakthrough Initiatives are a suite of scientific and technological programs looking for life in the Universe.

Preliminary orbital calculations suggest that the object came from the approximate direction of the bright star Vega, in the northern constellation of Lyra. However, it took so long for the interstellar object to make the journey - even at the speed of about 59,000 miles per hour (26.4 kilometers per
second) -- that Vega was not near that position when the asteroid was there about 300,000 years ago.

Astronomers estimate that an interstellar asteroid similar to ‘Oumuamua passes through the inner solar system about once per year, but they are faint and hard to spot and have been missed until now. It is only recently that survey telescopes, such as Pan-STARRS, are powerful enough to have a chance to discover them.

“What a fascinating discovery this is!” said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory, Pasadena, California. “It’s a strange visitor from a faraway star system, shaped like nothing we’ve ever seen in our own solar system neighborhood.

Contacts and sources:
 Breakthrough Initiatives
Janet Wootten, Rubenstein Communications, Inc.

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